IMPERVIOUS LAYER OF BENTONITE-MIXED SOIL AND ITS EXECUTION METHOD

摘要

PROBLEM TO BE SOLVED: To prevent the generation of a dust, maintaining the efficiency of pumping in a spraying hose, to improve even adhesion in spraying and to sufficiently demonstrate an impervious performance. SOLUTION: When the impervious layer is executed by spraying bentonite- mixed soil in which sand and bentonite are mixed, water at a sand weight ratio of 2 to 10% is added as pre-mixed water in mixing of sand and bentonite and pumped in a spraying hose 11. Water in quantity, in which the section of pre-mixed water is subtracted from a material being sent in the spraying hose 11, is added to the material, aiming at the water content of 10 to 30% of sprayed bentonite-mixed soil in a spraying nozzle 13 or in the vicinity of the spraying nozzle.